Single photons in nonlinear photonic crystals and studies on electromagnetic knots

Dirk Englund, Ilya Fushman, Andrei Faraon +1 more

Kevin J. Resch, Jeff S. Lundeen, Aephraim M. Steinberg

It is shown that quantum interference with classical beams may be used to suppress or enhance the rate of spontaneous photon-pair production from a nonlinear crystal. Sum-frequency generation of the classical beams is simultaneously enhanced or suppressed via interference with a classical pump. In the extreme case, a crystal which is transparent to individual photons may block all photon pairs, converting them to 2w. This constitutes a coherent nonlinear response at the single-photon level, enhanced by a factor of approximately 10 10 Experimental data and a theoretical description are presented, and an attempt is made to delineate the classical and quantum aspects of these effects.

William T. M. Irvine, M. J. A. de Dood, Dirk Bouwmeester

Gyeong-il Kweon, N. M. Lawandy

A I Garifullin, R. Kh. Gainutdinov, Хамадеев Марат Актасович

Subject of study. A single InAs quantum dot in a one-dimensional photonic crystal based on GaAs is examined. Aim of study. The aim of this study is to develop a method for controlling photon emission frequencies from a single quantum dot within a one-dimensional photonic crystal based on changes in the electromagnetic mass of an electron in the photonic crystal medium. Method. The proposed approach leverages the effect of changing the electromagnetic mass of an electron in the photonic crystal medium, manifesting as corrections to electron energy levels depending on the optical density of the medium. To control this density, the injection of free charge carriers and the quadratic electro-optic Kerr effect are proposed. Main results. The feasibility of in situ control of photon emission frequencies from a quantum dot was demonstrated using quantum transitions between the p- and s-states of a hydrogen-like InAs quantum dot situated in the air voids of a one-dimensional GaAs photonic crystal. This control is achieved through the effect of changing the electromagnetic mass of an electron, as well as tuning the refractive index of the photonic crystal via free charge carrier injection and the electro-optic Kerr effect. Calculations indicate that the photon energy control range available in experiments is limited to several tens of microelectronvolts, restricting practical applicability, and the observed displacement effect is smaller than experimentally recorded values. However, the energy level displacement, influenced by the quantum electrodynamic effect under investigation, exhibits a quadratic dependence on the refractive index of the material forming the photonic crystal. Consequently, the method is expected to scale significantly with increasing optical density. Such photonic crystals could be constructed using metamaterials with a high refractive index. Practical significance. The findings of this study, centered on developing a method for controlling photon emission frequencies from a single quantum dot in a one-dimensional photonic crystal, lay the groundwork for photon-emitter interfaces. These interfaces will incorporate key quantum functionalities, including photonic qubits, single-photon light sources, and nonlinear quantum photon-photon gates.

Yongqiang Chen, Kejia Zhu, Yunhui Li +4 more

We experimentally and theoretically investigate the nonlinear electromagnetic properties of a microstrip photonic crystal (PC) cavity with embedded electromagnetic-induced-transparency (EIT)-like meta-atoms. A bistable response, with threshold of low to −6.1 dBm and the transmission contrast of up to 4.0 dB, is conceptually demonstrated with a varactor as the nonlinear medium inclusion. Such low-threshold and high-contrast transmission action comes from the composite PC-EIT mechanism, which possesses sharper features and stronger localization of the electromagnetic field than either PC cavity or EIT-like meta-atoms. This mechanism will be useful for all-optical signal processing with advanced materials.